[thirdparty/gcc.git] / zlib / inftrees.c

/* inftrees.c -- generate Huffman trees for efficient decoding
 * Copyright (C) 1995-2017 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#include "zutil.h"
#include "inftrees.h"

#define MAXBITS 15

const char inflate_copyright[] =
   " inflate 1.2.11 Copyright 1995-2017 Mark Adler ";
/*
  If you use the zlib library in a product, an acknowledgment is welcome
  in the documentation of your product. If for some reason you cannot
  include such an acknowledgment, I would appreciate that you keep this
  copyright string in the executable of your product.
 */

/*
   Build a set of tables to decode the provided canonical Huffman code.
   The code lengths are lens[0..codes-1].  The result starts at *table,
   whose indices are 0..2^bits-1.  work is a writable array of at least
   lens shorts, which is used as a work area.  type is the type of code
   to be generated, CODES, LENS, or DISTS.  On return, zero is success,
   -1 is an invalid code, and +1 means that ENOUGH isn't enough.  table
   on return points to the next available entry's address.  bits is the
   requested root table index bits, and on return it is the actual root
   table index bits.  It will differ if the request is greater than the
   longest code or if it is less than the shortest code.
 */
int ZLIB_INTERNAL inflate_table(type, lens, codes, table, bits, work)
codetype type;
unsigned short FAR *lens;
unsigned codes;
code FAR * FAR *table;
unsigned FAR *bits;
unsigned short FAR *work;
{
    unsigned len;               /* a code's length in bits */
    unsigned sym;               /* index of code symbols */
    unsigned min, max;          /* minimum and maximum code lengths */
    unsigned root;              /* number of index bits for root table */
    unsigned curr;              /* number of index bits for current table */
    unsigned drop;              /* code bits to drop for sub-table */
    int left;                   /* number of prefix codes available */
    unsigned used;              /* code entries in table used */
    unsigned huff;              /* Huffman code */
    unsigned incr;              /* for incrementing code, index */
    unsigned fill;              /* index for replicating entries */
    unsigned low;               /* low bits for current root entry */
    unsigned mask;              /* mask for low root bits */
    code here;                  /* table entry for duplication */
    code FAR *next;             /* next available space in table */
    const unsigned short FAR *base;     /* base value table to use */
    const unsigned short FAR *extra;    /* extra bits table to use */
    unsigned match;             /* use base and extra for symbol >= match */
    unsigned short count[MAXBITS+1];    /* number of codes of each length */
    unsigned short offs[MAXBITS+1];     /* offsets in table for each length */
    static const unsigned short lbase[31] = { /* Length codes 257..285 base */
        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
    static const unsigned short lext[31] = { /* Length codes 257..285 extra */
        16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 77, 202};
    static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
        8193, 12289, 16385, 24577, 0, 0};
    static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
        16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
        23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
        28, 28, 29, 29, 64, 64};

    /*
       Process a set of code lengths to create a canonical Huffman code.  The
       code lengths are lens[0..codes-1].  Each length corresponds to the
       symbols 0..codes-1.  The Huffman code is generated by first sorting the
       symbols by length from short to long, and retaining the symbol order
       for codes with equal lengths.  Then the code starts with all zero bits
       for the first code of the shortest length, and the codes are integer
       increments for the same length, and zeros are appended as the length
       increases.  For the deflate format, these bits are stored backwards
       from their more natural integer increment ordering, and so when the
       decoding tables are built in the large loop below, the integer codes
       are incremented backwards.

       This routine assumes, but does not check, that all of the entries in
       lens[] are in the range 0..MAXBITS.  The caller must assure this.
       1..MAXBITS is interpreted as that code length.  zero means that that
       symbol does not occur in this code.

       The codes are sorted by computing a count of codes for each length,
       creating from that a table of starting indices for each length in the
       sorted table, and then entering the symbols in order in the sorted
       table.  The sorted table is work[], with that space being provided by
       the caller.

       The length counts are used for other purposes as well, i.e. finding
       the minimum and maximum length codes, determining if there are any
       codes at all, checking for a valid set of lengths, and looking ahead
       at length counts to determine sub-table sizes when building the
       decoding tables.
     */

    /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
    for (len = 0; len <= MAXBITS; len++)
        count[len] = 0;
    for (sym = 0; sym < codes; sym++)
        count[lens[sym]]++;

    /* bound code lengths, force root to be within code lengths */
    root = *bits;
    for (max = MAXBITS; max >= 1; max--)
        if (count[max] != 0) break;
    if (root > max) root = max;
    if (max == 0) {                     /* no symbols to code at all */
        here.op = (unsigned char)64;    /* invalid code marker */
        here.bits = (unsigned char)1;
        here.val = (unsigned short)0;
        *(*table)++ = here;             /* make a table to force an error */
        *(*table)++ = here;
        *bits = 1;
        return 0;     /* no symbols, but wait for decoding to report error */
    }
    for (min = 1; min < max; min++)
        if (count[min] != 0) break;
    if (root < min) root = min;

    /* check for an over-subscribed or incomplete set of lengths */
    left = 1;
    for (len = 1; len <= MAXBITS; len++) {
        left <<= 1;
        left -= count[len];
        if (left < 0) return -1;        /* over-subscribed */
    }
    if (left > 0 && (type == CODES || max != 1))
        return -1;                      /* incomplete set */

    /* generate offsets into symbol table for each length for sorting */
    offs[1] = 0;
    for (len = 1; len < MAXBITS; len++)
        offs[len + 1] = offs[len] + count[len];

    /* sort symbols by length, by symbol order within each length */
    for (sym = 0; sym < codes; sym++)
        if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;

    /*
       Create and fill in decoding tables.  In this loop, the table being
       filled is at next and has curr index bits.  The code being used is huff
       with length len.  That code is converted to an index by dropping drop
       bits off of the bottom.  For codes where len is less than drop + curr,
       those top drop + curr - len bits are incremented through all values to
       fill the table with replicated entries.

       root is the number of index bits for the root table.  When len exceeds
       root, sub-tables are created pointed to by the root entry with an index
       of the low root bits of huff.  This is saved in low to check for when a
       new sub-table should be started.  drop is zero when the root table is
       being filled, and drop is root when sub-tables are being filled.

       When a new sub-table is needed, it is necessary to look ahead in the
       code lengths to determine what size sub-table is needed.  The length
       counts are used for this, and so count[] is decremented as codes are
       entered in the tables.

       used keeps track of how many table entries have been allocated from the
       provided *table space.  It is checked for LENS and DIST tables against
       the constants ENOUGH_LENS and ENOUGH_DISTS to guard against changes in
       the initial root table size constants.  See the comments in inftrees.h
       for more information.

       sym increments through all symbols, and the loop terminates when
       all codes of length max, i.e. all codes, have been processed.  This
       routine permits incomplete codes, so another loop after this one fills
       in the rest of the decoding tables with invalid code markers.
     */

    /* set up for code type */
    switch (type) {
    case CODES:
        base = extra = work;    /* dummy value--not used */
        match = 20;
        break;
    case LENS:
        base = lbase;
        extra = lext;
        match = 257;
        break;
    default:    /* DISTS */
        base = dbase;
        extra = dext;
        match = 0;
    }

    /* initialize state for loop */
    huff = 0;                   /* starting code */
    sym = 0;                    /* starting code symbol */
    len = min;                  /* starting code length */
    next = *table;              /* current table to fill in */
    curr = root;                /* current table index bits */
    drop = 0;                   /* current bits to drop from code for index */
    low = (unsigned)(-1);       /* trigger new sub-table when len > root */
    used = 1U << root;          /* use root table entries */
    mask = used - 1;            /* mask for comparing low */

    /* check available table space */
    if ((type == LENS && used > ENOUGH_LENS) ||
        (type == DISTS && used > ENOUGH_DISTS))
        return 1;

    /* process all codes and make table entries */
    for (;;) {
        /* create table entry */
        here.bits = (unsigned char)(len - drop);
        if (work[sym] + 1U < match) {
            here.op = (unsigned char)0;
            here.val = work[sym];
        }
        else if (work[sym] >= match) {
            here.op = (unsigned char)(extra[work[sym] - match]);
            here.val = base[work[sym] - match];
        }
        else {
            here.op = (unsigned char)(32 + 64);         /* end of block */
            here.val = 0;
        }

        /* replicate for those indices with low len bits equal to huff */
        incr = 1U << (len - drop);
        fill = 1U << curr;
        min = fill;                 /* save offset to next table */
        do {
            fill -= incr;
            next[(huff >> drop) + fill] = here;
        } while (fill != 0);

        /* backwards increment the len-bit code huff */
        incr = 1U << (len - 1);
        while (huff & incr)
            incr >>= 1;
        if (incr != 0) {
            huff &= incr - 1;
            huff += incr;
        }
        else
            huff = 0;

        /* go to next symbol, update count, len */
        sym++;
        if (--(count[len]) == 0) {
            if (len == max) break;
            len = lens[work[sym]];
        }

        /* create new sub-table if needed */
        if (len > root && (huff & mask) != low) {
            /* if first time, transition to sub-tables */
            if (drop == 0)
                drop = root;

            /* increment past last table */
            next += min;            /* here min is 1 << curr */

            /* determine length of next table */
            curr = len - drop;
            left = (int)(1 << curr);
            while (curr + drop < max) {
                left -= count[curr + drop];
                if (left <= 0) break;
                curr++;
                left <<= 1;
            }

            /* check for enough space */
            used += 1U << curr;
            if ((type == LENS && used > ENOUGH_LENS) ||
                (type == DISTS && used > ENOUGH_DISTS))
                return 1;

            /* point entry in root table to sub-table */
            low = huff & mask;
            (*table)[low].op = (unsigned char)curr;
            (*table)[low].bits = (unsigned char)root;
            (*table)[low].val = (unsigned short)(next - *table);
        }
    }

    /* fill in remaining table entry if code is incomplete (guaranteed to have
       at most one remaining entry, since if the code is incomplete, the
       maximum code length that was allowed to get this far is one bit) */
    if (huff != 0) {
        here.op = (unsigned char)64;            /* invalid code marker */
        here.bits = (unsigned char)(len - drop);
        here.val = (unsigned short)0;
        next[huff] = here;
    }

    /* set return parameters */
    *table += used;
    *bits = root;
    return 0;
}
Commit	Line	Data
d8b6dda4	1	/* inftrees.c -- generate Huffman trees for efficient decoding
1e5dce21	2	* Copyright (C) 1995-2017 Mark Adler
87a2b23a	3	* For conditions of distribution and use, see copyright notice in zlib.h
d8b6dda4	4	*/
	5
	6	#include "zutil.h"
	7	#include "inftrees.h"
	8
87a2b23a	9	#define MAXBITS 15
d8b6dda4	10
d8b6dda4	11	const char inflate_copyright[] =
239eb531	12	" inflate 1.2.11 Copyright 1995-2017 Mark Adler ";
d8b6dda4	13	/*
	14	If you use the zlib library in a product, an acknowledgment is welcome
	15	in the documentation of your product. If for some reason you cannot
	16	include such an acknowledgment, I would appreciate that you keep this
	17	copyright string in the executable of your product.
	18	*/
d8b6dda4	19
d8b6dda4	20	/*
87a2b23a	21	Build a set of tables to decode the provided canonical Huffman code.
	22	The code lengths are lens[0..codes-1]. The result starts at *table,
	23	whose indices are 0..2^bits-1. work is a writable array of at least
	24	lens shorts, which is used as a work area. type is the type of code
	25	to be generated, CODES, LENS, or DISTS. On return, zero is success,
	26	-1 is an invalid code, and +1 means that ENOUGH isn't enough. table
	27	on return points to the next available entry's address. bits is the
	28	requested root table index bits, and on return it is the actual root
	29	table index bits. It will differ if the request is greater than the
	30	longest code or if it is less than the shortest code.
d8b6dda4	31	*/
1f54c5b6	32	int ZLIB_INTERNAL inflate_table(type, lens, codes, table, bits, work)
87a2b23a	33	codetype type;
	34	unsigned short FAR *lens;
	35	unsigned codes;
	36	code FAR * FAR *table;
	37	unsigned FAR *bits;
	38	unsigned short FAR *work;
d8b6dda4	39	{
87a2b23a	40	unsigned len; /* a code's length in bits */
	41	unsigned sym; /* index of code symbols */
	42	unsigned min, max; /* minimum and maximum code lengths */
	43	unsigned root; /* number of index bits for root table */
	44	unsigned curr; /* number of index bits for current table */
	45	unsigned drop; /* code bits to drop for sub-table */
	46	int left; /* number of prefix codes available */
	47	unsigned used; /* code entries in table used */
	48	unsigned huff; /* Huffman code */
	49	unsigned incr; /* for incrementing code, index */
	50	unsigned fill; /* index for replicating entries */
	51	unsigned low; /* low bits for current root entry */
	52	unsigned mask; /* mask for low root bits */
1f54c5b6	53	code here; /* table entry for duplication */
87a2b23a	54	code FAR next; / next available space in table */
	55	const unsigned short FAR base; / base value table to use */
	56	const unsigned short FAR extra; / extra bits table to use */
1e5dce21	57	unsigned match; /* use base and extra for symbol >= match */
87a2b23a	58	unsigned short count[MAXBITS+1]; /* number of codes of each length */
	59	unsigned short offs[MAXBITS+1]; /* offsets in table for each length */
	60	static const unsigned short lbase[31] = { /* Length codes 257..285 base */
	61	3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
	62	35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
	63	static const unsigned short lext[31] = { /* Length codes 257..285 extra */
	64	16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
239eb531	65	19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 77, 202};
87a2b23a	66	static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
	67	1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
	68	257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
	69	8193, 12289, 16385, 24577, 0, 0};
	70	static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
	71	16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
	72	23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
	73	28, 28, 29, 29, 64, 64};
	74
	75	/*
	76	Process a set of code lengths to create a canonical Huffman code. The
	77	code lengths are lens[0..codes-1]. Each length corresponds to the
	78	symbols 0..codes-1. The Huffman code is generated by first sorting the
	79	symbols by length from short to long, and retaining the symbol order
	80	for codes with equal lengths. Then the code starts with all zero bits
	81	for the first code of the shortest length, and the codes are integer
	82	increments for the same length, and zeros are appended as the length
	83	increases. For the deflate format, these bits are stored backwards
	84	from their more natural integer increment ordering, and so when the
	85	decoding tables are built in the large loop below, the integer codes
	86	are incremented backwards.
	87
	88	This routine assumes, but does not check, that all of the entries in
	89	lens[] are in the range 0..MAXBITS. The caller must assure this.
	90	1..MAXBITS is interpreted as that code length. zero means that that
	91	symbol does not occur in this code.
	92
	93	The codes are sorted by computing a count of codes for each length,
	94	creating from that a table of starting indices for each length in the
	95	sorted table, and then entering the symbols in order in the sorted
	96	table. The sorted table is work[], with that space being provided by
	97	the caller.
	98
	99	The length counts are used for other purposes as well, i.e. finding
	100	the minimum and maximum length codes, determining if there are any
	101	codes at all, checking for a valid set of lengths, and looking ahead
	102	at length counts to determine sub-table sizes when building the
	103	decoding tables.
	104	*/
	105
	106	/* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
	107	for (len = 0; len <= MAXBITS; len++)
	108	count[len] = 0;
	109	for (sym = 0; sym < codes; sym++)
	110	count[lens[sym]]++;
	111
	112	/* bound code lengths, force root to be within code lengths */
	113	root = *bits;
	114	for (max = MAXBITS; max >= 1; max--)
	115	if (count[max] != 0) break;
	116	if (root > max) root = max;
d919a5db	117	if (max == 0) { /* no symbols to code at all */
1f54c5b6	118	here.op = (unsigned char)64; /* invalid code marker */
	119	here.bits = (unsigned char)1;
	120	here.val = (unsigned short)0;
	121	(table)++ = here; /* make a table to force an error */
	122	(table)++ = here;
d919a5db	123	*bits = 1;
	124	return 0; /* no symbols, but wait for decoding to report error */
	125	}
1f54c5b6	126	for (min = 1; min < max; min++)
87a2b23a	127	if (count[min] != 0) break;
	128	if (root < min) root = min;
	129
	130	/* check for an over-subscribed or incomplete set of lengths */
	131	left = 1;
	132	for (len = 1; len <= MAXBITS; len++) {
	133	left <<= 1;
	134	left -= count[len];
	135	if (left < 0) return -1; /* over-subscribed */
	136	}
d919a5db	137	if (left > 0 && (type == CODES \|\| max != 1))
87a2b23a	138	return -1; /* incomplete set */
	139
	140	/* generate offsets into symbol table for each length for sorting */
	141	offs[1] = 0;
	142	for (len = 1; len < MAXBITS; len++)
	143	offs[len + 1] = offs[len] + count[len];
	144
	145	/* sort symbols by length, by symbol order within each length */
	146	for (sym = 0; sym < codes; sym++)
	147	if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
	148
	149	/*
	150	Create and fill in decoding tables. In this loop, the table being
	151	filled is at next and has curr index bits. The code being used is huff
	152	with length len. That code is converted to an index by dropping drop
	153	bits off of the bottom. For codes where len is less than drop + curr,
	154	those top drop + curr - len bits are incremented through all values to
	155	fill the table with replicated entries.
	156
	157	root is the number of index bits for the root table. When len exceeds
	158	root, sub-tables are created pointed to by the root entry with an index
	159	of the low root bits of huff. This is saved in low to check for when a
	160	new sub-table should be started. drop is zero when the root table is
	161	being filled, and drop is root when sub-tables are being filled.
	162
	163	When a new sub-table is needed, it is necessary to look ahead in the
	164	code lengths to determine what size sub-table is needed. The length
	165	counts are used for this, and so count[] is decremented as codes are
	166	entered in the tables.
	167
	168	used keeps track of how many table entries have been allocated from the
1f54c5b6	169	provided *table space. It is checked for LENS and DIST tables against
	170	the constants ENOUGH_LENS and ENOUGH_DISTS to guard against changes in
	171	the initial root table size constants. See the comments in inftrees.h
	172	for more information.
87a2b23a	173
	174	sym increments through all symbols, and the loop terminates when
	175	all codes of length max, i.e. all codes, have been processed. This
	176	routine permits incomplete codes, so another loop after this one fills
	177	in the rest of the decoding tables with invalid code markers.
	178	*/
	179
	180	/* set up for code type */
	181	switch (type) {
	182	case CODES:
	183	base = extra = work; /* dummy value--not used */
1e5dce21	184	match = 20;
87a2b23a	185	break;
	186	case LENS:
	187	base = lbase;
87a2b23a	188	extra = lext;
1e5dce21	189	match = 257;
87a2b23a	190	break;
1e5dce21	191	default: /* DISTS */
87a2b23a	192	base = dbase;
87a2b23a	193	extra = dext;
1e5dce21	194	match = 0;
87a2b23a	195	}
d8b6dda4	196
87a2b23a	197	/* initialize state for loop */
	198	huff = 0; /* starting code */
	199	sym = 0; /* starting code symbol */
	200	len = min; /* starting code length */
	201	next = table; / current table to fill in */
	202	curr = root; /* current table index bits */
	203	drop = 0; /* current bits to drop from code for index */
	204	low = (unsigned)(-1); /* trigger new sub-table when len > root */
	205	used = 1U << root; /* use root table entries */
	206	mask = used - 1; /* mask for comparing low */
	207
	208	/* check available table space */
4b57a6ef	209	if ((type == LENS && used > ENOUGH_LENS) \|\|
4b57a6ef	210	(type == DISTS && used > ENOUGH_DISTS))
87a2b23a	211	return 1;
	212
	213	/* process all codes and make table entries */
	214	for (;;) {
	215	/* create table entry */
1f54c5b6	216	here.bits = (unsigned char)(len - drop);
1e5dce21	217	if (work[sym] + 1U < match) {
1f54c5b6	218	here.op = (unsigned char)0;
1f54c5b6	219	here.val = work[sym];
d8b6dda4	220	}
1e5dce21	221	else if (work[sym] >= match) {
	222	here.op = (unsigned char)(extra[work[sym] - match]);
	223	here.val = base[work[sym] - match];
87a2b23a	224	}
87a2b23a	225	else {
1f54c5b6	226	here.op = (unsigned char)(32 + 64); /* end of block */
1f54c5b6	227	here.val = 0;
d8b6dda4	228	}
d8b6dda4	229
87a2b23a	230	/* replicate for those indices with low len bits equal to huff */
	231	incr = 1U << (len - drop);
	232	fill = 1U << curr;
d919a5db	233	min = fill; /* save offset to next table */
87a2b23a	234	do {
87a2b23a	235	fill -= incr;
1f54c5b6	236	next[(huff >> drop) + fill] = here;
87a2b23a	237	} while (fill != 0);
	238
	239	/* backwards increment the len-bit code huff */
	240	incr = 1U << (len - 1);
	241	while (huff & incr)
	242	incr >>= 1;
	243	if (incr != 0) {
	244	huff &= incr - 1;
	245	huff += incr;
	246	}
	247	else
	248	huff = 0;
d8b6dda4	249
87a2b23a	250	/* go to next symbol, update count, len */
	251	sym++;
	252	if (--(count[len]) == 0) {
	253	if (len == max) break;
	254	len = lens[work[sym]];
	255	}
d8b6dda4	256
87a2b23a	257	/* create new sub-table if needed */
	258	if (len > root && (huff & mask) != low) {
	259	/* if first time, transition to sub-tables */
	260	if (drop == 0)
	261	drop = root;
	262
	263	/* increment past last table */
d919a5db	264	next += min; /* here min is 1 << curr */
87a2b23a	265
	266	/* determine length of next table */
	267	curr = len - drop;
	268	left = (int)(1 << curr);
	269	while (curr + drop < max) {
	270	left -= count[curr + drop];
	271	if (left <= 0) break;
	272	curr++;
	273	left <<= 1;
	274	}
d8b6dda4	275
87a2b23a	276	/* check for enough space */
87a2b23a	277	used += 1U << curr;
4b57a6ef	278	if ((type == LENS && used > ENOUGH_LENS) \|\|
4b57a6ef	279	(type == DISTS && used > ENOUGH_DISTS))
87a2b23a	280	return 1;
d8b6dda4	281
87a2b23a	282	/* point entry in root table to sub-table */
	283	low = huff & mask;
	284	(*table)[low].op = (unsigned char)curr;
	285	(*table)[low].bits = (unsigned char)root;
	286	(table)[low].val = (unsigned short)(next - table);
	287	}
d8b6dda4	288	}
d8b6dda4	289
75e1829f	290	/* fill in remaining table entry if code is incomplete (guaranteed to have
	291	at most one remaining entry, since if the code is incomplete, the
	292	maximum code length that was allowed to get this far is one bit) */
	293	if (huff != 0) {
	294	here.op = (unsigned char)64; /* invalid code marker */
	295	here.bits = (unsigned char)(len - drop);
	296	here.val = (unsigned short)0;
	297	next[huff] = here;
d8b6dda4	298	}
d8b6dda4	299
87a2b23a	300	/* set return parameters */
	301	*table += used;
	302	*bits = root;
	303	return 0;
d8b6dda4	304	}